This week’s episode of Project Runway has something for fans of The Big Bang Theory – actress Kaley Cuoco serves as a guest judge on the reality fashion competition.

“I’m thrilled to be here as a judge on Project Runway,” Cuocu gushes in a behind-the-scenes video. “It’s one of my favorite shows. It’s wild to watch it for so many years and then go into the actual room and see the runway. It’s crazy.”

A teaser clip from Lifetime also promises that this week’s challenge will involve “some sole searching,” as the designer contestants are tasked with creating a look inspired by footwear from the fashion closet at Marie Claire magazine. “Many women say it’s the most important fashion accessory of all,” muses Tim Gunn. “Shoes!” The designers then face off in a fashion pop quiz that determines the order in which they get to pick a pair of shoes.

Click on to see what Cuoco says were her criteria for guest judging the top 10. Bonus clip: Do you know what inspired Christian Louboutin’s signature red soles? Watch the second video for the answer.